Debris-filter materials principally for automatic swimming pool cleaners

ABSTRACT

Debris filters for automatic swimming pool cleaners may be formed of metal, carbon fibers, or composites more rigid than soft nylon bags. In at least one version, the filter may be made of, or include, steel or stainless steel. Non-uniform sizes, densities, and/or shapes of openings in the filtration material may be created to provide different levels of filtration in a single device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of allowed U.S. patent applicationSer. No. 16/806,403, filed Mar. 2, 2020 (the “Parent Application”),which Parent Application in turn claims the benefit of and priority to(1) U.S. Provisional Patent Application Ser. No. 62/844,422, filed May7, 2019, and (2) U.S. Provisional Patent Application Ser. No.62/823,134, filed Mar. 25, 2019, the entire contents of both of whichprovisional applications, as well as of the Parent Application, arehereby incorporated herein by this reference.

FIELD OF THE INVENTION

This invention relates to cleaners of water-containing vessels such asswimming pools or spas and more particularly, although not necessarilyexclusively, to materials used to construct debris filters for cleanersconfigured to move autonomously within the vessels.

BACKGROUND OF THE INVENTION

Automatic swimming pool cleaners (APCs) are well known. These cleanersoften are categorized as either “hydraulic” or “robotic” (or“electric”), depending on the source of their motive power. Hydrauliccleaners, for example, typically use pressurized (or depressurized)water to effect their movement within pools, whereas robotic cleanerstypically utilize an electric motor to cause their movement. Moreover,hydraulic cleaners frequently are subcategorized as either“pressure-side” or “suction-side” devices, with pressure-side cleanersreceiving pressurized water output from an associated water-circulationpump and suction-side cleaners, by contrast, being connected to an inletof the pump.

Suction-side APCs conventionally lack any on-board debris filters,instead allowing the debris to pass through their bodies, throughconnecting hoses, to fixed-location filters associated with thewater-circulation system of the pool. Pressure-side and robotic cleanersgenerally include debris filters that move together with the cleaners:Filters of pressure-side APCs frequently are positioned externally of,but are attached to, the cleaner bodies, whereas debris filters ofrobotic cleaners often are positioned within the cleaner bodies.

As noted in U.S. Pat. No. 8,784,652 to Rief, et al., these debrisfilters conventionally are “flexible nylon bags typically made from asoft material.” See Rief, col. 2, ll. 19-20. Although the Rief patentdiscusses using a “rigid debris-collection canister,” see id., col. 3,ll. 18-19, the rigid canister contains a seemingly conventional soft“fine-mesh container” or “fine mesh insert” in order “to entrap finedebris” therein. See id., col. 6, ll. 58-60; col. 7, ll. 12-15.

U.S. Pat. No. 9,909,334 to Maggeni, et al., details a robotic APC havingan internal filter. According to the Maggeni patent, the filter “can bemade of any flexible or non-flexible filtering material” including“woven fiber mesh, non-woven mesh, polymer, textile, paper, orcombinations.” See Maggeni, col. 6, ll. 47-49. The filter also isdescribed as comprising “fabric.” See id., l. 33.

The soft materials disclosed in the Rief and Maggeni patents generallyperform satisfactorily in APCs, but are not without disadvantages. Whenformed as bags, for example, the soft materials “have a tendency to becaught under the cleaner wheels and be damaged.” See Rief, col. 2, ll.20-21. They also are susceptible to tearing, chemical damage, and beingimproperly installed on APCs. See id., ll. 22-25. Further, states theRief patent, external flexible bags may “act like sails” in the pool and“are a hindrance to pool-cleaner movement,” and because the bags arecollapsible, they often are hard to clean. See id., ll. 28 and 32-33.

SUMMARY OF THE INVENTION

The present invention seeks to provide debris filters for APCs thatresolve some or all of these issues. In particular, filters of thepresent invention may be formed of metal, carbon fibers, or compositesmore rigid than soft nylon bags. In at least one version, the filter maybe made of, or include, steel or stainless steel.

In some cases, filters of the present invention could be made ofconnected strands of, e.g., metal so as to form a mesh. Beneficially,however, a solid sheet of, e.g., metal may be screened, etched, punched,stamped, or stenciled so as to remove portions of the sheet and thussimulate a mesh. Such activities advantageously may be performedchemically, although mechanical or other approaches (e.g. laser cuttingor die cutting) conceivably may be used instead.

For example, a screen including solid areas and holes and resistant to aparticular chemical substance may be placed atop the solid sheet ofmetal (which, by contrast, may be corroded or etched by the chemicalsubstance). The chemical substance may then be applied to the screen,whose solid areas will block transfer of the substance to the metalsheet and whose holes will allow transfer of the substance to the metalsheet. The transferred chemical substance will corrode or etch the metalsheet, producing openings in it aligned with the holes of the screen.

In one version of a metal sheet, multiple openings each having size ofapproximately 0.2 mm may be formed. Openings of this size are compatiblewith water-filtration requirements for most APCs. The process allows forformation of openings of different sizes, however, merely by changingthe screen. As well, screens could be used in which their holesthemselves are different sizes (and/or shapes), hence producingnon-uniform openings in the metal sheet. Screens alternatively oradditionally may include different densities of openings.

Incorporating non-uniform openings into a sheet allows for “evolutive”filtering to occur. Utilizing sheets such as these, different regions ofa filter may provide different levels of filtration for the debris-ladenwater they encounter. For example, relatively dirty water may bedirected to regions providing coarser filtration, while cleaner watermay be directed to regions providing finer filtration. Hence, a singlefilter may perform two or more levels of filtration in use, potentiallyavoiding any need for a separate pre-filter or second filtering device.

Because metals typically have greater rigidity that soft nylon bags, forexample, forming such a metal filter also may produce a structure thatis less likely to collapse than is a nylon bag. The enhanced rigidity ofthe metal filter additionally may reduce the amount of rigid framingotherwise needed to create a hybrid mesh/frame object, and the metalfilter may be more durable and less likely to tear or be subject tocorrosion because of chemicals present in pool water or solar radiation.At least some filters may include both metal and fabric if appropriateor desired. Alternatively or additionally, semi-rigid or rigid plasticsconceivably could be included.

It thus is an optional, non-exclusive object of the present invention toprovide debris filters formed of or including metal, carbon fibers, orcomposite materials.

It is another optional, non-exclusive object of the present invention toprovide debris filters, at least portions of which are created from asolid sheet of material into which openings have been formed.

It is a further optional, non-exclusive object of the present inventionto provide debris filters whose openings are not uniform in size, shape,or both size and shape.

It is also an optional, non-exclusive object of the present invention toprovide debris filters including solid sheets of metal that have beentreated chemically to create openings.

It is, moreover, an optional, non-exclusive object of the presentinvention to provide debris filters in which sheets with openings areattached to framing for use in or with APCs.

Other objects, features, and advantages of the present invention will beapparent to persons skilled in the relevant fields with reference to theremaining text and the drawings of this application.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary debris filter of thepresent invention.

FIG. 2 is an exploded view of primary components of the debris filter ofFIG.

FIG. 3 is an exploded view of an exemplary metal sheets useful to form aprimary component of the debris filter of FIGS. 1-2 .

DETAILED DESCRIPTION

Illustrated in FIG. 1 is an exemplary debris filter 10 of the presentinvention. Debris-laden water may enter filter 10, with filter 10stopping some of the debris before allowing the (filtered) water toexit. Filter 10 is designed for use within an APC, although itconceivably may be employed for other purposes. At least some versionsof filter 10 may (but need not necessarily) resemble and function likethe filtering device of U.S. Pat. No. 8,393,030 to Pichon, et al.

As shown principally in FIG. 2 , filter 10 may include frame 11 and mesh12. Frame 11 preferably is sufficiently rigid to retain its shape at alltimes and typically (but not necessarily) is molded or otherwise formedof plastic material. FIGS. 1-3 depict frame 11 as having a particularcomplex shape, although other complex or non-complex shapes may bedevised instead. In some instances frame 11 may compriseintegrally-molded main longitudinal and lateral support beams 14 and 16,respectively, as well as additional support beams 18 and handle 19, forexample.

Some or all of mesh 12 may be formed of fabric or other conventionalmaterials, in which case the term “mesh” may be used in the standardsense of being an interwoven or intertwined structure. Preferably,however, mesh 12 is a structure formed by one or more sheets of metal(or other material) and not interwoven or intertwined. Preferred mesh 12thus may be said to simulate conventional “mesh,” as noted earlier inthis application.

FIG. 3 illustrates one version of mesh 12 formed by three pieces ofmetal such as (but not limited to) steel or stainless steel. Centralportion 12A is shown as bent at vertex 20 to form a shape approximatingthat of interior 22 of frame 11. Mesh 12 additionally may include sideportions 12B-C.

In some versions of filter 10, portions 12A-C may be connectedtogether—as shown in FIG. 2 —before being attached to frame 11. Portions12A-C need not necessarily be interconnected, however, and instead maybe attached only to frame 11. Likewise, mesh 12 need not necessarily beformed by three pieces of material, as more or fewer pieces may beemployed. Additionally, mesh 12 may be attached to either the interioror exterior of frame 11 in any appropriate manner, including (but notlimited to) overmolding frame 11 onto mesh 12 or gluing the twocomponents together.

A multiplicity of openings 24 in sheets of mesh 12 are depicted in FIGS.1-3 . Openings 24 may be of any desired shapes, sizes, and densities. Asillustrated, for example, side portions 12B-C contain openings 24 thatare substantially circular and uniformly distributed. By contrast,central portion 12A may, if desired, contain both these types ofopenings 24 as well as generally square openings 24A and generallyrectangular openings 24B distributed in various patterns (including, forexample, annular and spiral patterns). Clear from central portion 12A isthat the openings 24 need not be uniformly distributed about a sheet,and indeed that significant areas (e.g., area 26) of the sheet mayremain solid or have few openings 24. Accordingly, filter 10 may provide“evolutive” filtering of fluid, with different levels of filtrationoccurring depending on whether debris-laden fluid encounters an areasuch as area 26, in which few openings 24 exist, or an area such as area30, in which many openings 24 are present. Placement, sizes, and shapesof openings 24 additionally may facilitate overmolding of frame 11 ontomesh 12 by providing regions of greater or lesser support, for example.

Exemplary concepts or combinations of features of the invention mayinclude:

-   -   A. A debris filter formed of or including metal, carbon fibers,        or composite materials.    -   B. An APC including a filter formed of or including metal,        carbon fibers, or composite materials.    -   C. An APC including a metal mesh filter.    -   D. A metal mesh filter formed from a solid sheet of material.    -   E. A metal mesh filter formed from a solid sheet of metal by        applying a corrosive chemical to a screen placed atop the metal        sheet.    -   F. A metal mesh filter whose opening sizes, densities, and/or        shapes are non-uniform.    -   G. A filter for an APC comprising a frame and mesh attached to        the frame, with the mesh comprising at least one integrated        sheet of material in which openings have been created.    -   H. A filter for an APC comprising a metal mesh to which a frame        is attached by overmolding or gluing.        These examples are not intended to be mutually exclusive,        exhaustive, or restrictive in any way, and the invention is not        limited to these example embodiments but rather encompasses all        possible modifications and variations within the scope of any        claims ultimately drafted and issued in connection with the        invention (and their equivalents). For avoidance of doubt, any        combination of features not physically impossible or expressly        identified as non-combinable herein may be within the scope of        the invention.

The entire contents of the Rief, Maggeni, and Pichon patents areincorporated herein by this reference. Further, although applicant hasdescribed filters for use with APCs, persons skilled in the relevantfield will recognize that the present invention may be employed in otherdevices such as (but not limited to) manual pool cleaners. Finally,references to “pools” and “swimming pools” herein may also refer to spasor other water containing vessels used for recreation or therapy and forwhich cleaning is needed or desired.

What is claimed is:
 1. A debris filter for an automatic swimming poolcleaner comprising at least one solid sheet of carbon fibers orcomposite materials in which openings have been created and a frame towhich the sheet of carbon fibers or composite materials is attached. 2.A debris filter for an automatic swimming pool cleaner formed of orincluding a sheet of carbon fibers or composite materials, with thesheet comprising first and second regions, each of the first and secondregions including a plurality of openings, with the plurality ofopenings included in the first region being of different size than theplurality of openings included in the second region.
 3. An automaticswimming pool cleaner comprising: a. a source of motive power formovement within a swimming pool; and b. a debris filter comprising: i. aframe sufficiently rigid to retain its shape in use; and ii. a mesh (A)attached to the frame and (B) comprising at least one sheet of carbonfibers or composite materials defining first and second regions in whichopenings exist, with at least some openings of the first regiondiffering in size, shape, or density from at least some openings of thesecond region.
 4. A method of cleaning a swimming pool, comprising: a.introducing into the swimming pool an automatic swimming pool cleanercomprising a debris filter comprising at least one solid sheet of metalin which openings have been formed, wherein the openings are ofnon-uniform size, shape or density; and b. causing water of the swimmingpool to enter the debris filter for filtering and thereafter to exit thedebris filter through the openings to return, directly or indirectly, tothe swimming pool.
 5. A method according to claim 4 in which the atleast one solid sheet of metal defines first and second regions, with atleast some openings of the first region differing in size from at leastsome openings of the second region.